Using JQuery or JavaScript to Obtain Default Behavior in a Form

All,
I have a packaged app - whose snippet is below and the form that displays shows ascending date (ascendingSort) and Title as the default items - I'd like to show the Publication Date (availableDate) and the descending date (descendingSort) as the two defaults - how in either Jquery or JavaScript can this be obtained - since this is a packaged app - I have to adjust this code via a secondary function: